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Date: Fri, 13 May 2022 12:31:36 -0700
From: Luis Chamberlain <mcgrof@kernel.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Ben Widawsky <ben.widawsky@intel.com>,
	Klaus Jensen <its@irrelevant.dk>, Josef Bacik <jbacik@fb.com>,
	Adam Manzanares <a.manzanares@samsung.com>,
	"linux-cxl@vger.kernel.org" <linux-cxl@vger.kernel.org>,
	Linux NVDIMM <nvdimm@lists.linux.dev>,
	"patches@lists.linux.dev" <patches@lists.linux.dev>,
	Alison Schofield <alison.schofield@intel.com>,
	Ira Weiny <ira.weiny@intel.com>,
	Vishal Verma <vishal.l.verma@intel.com>
Subject: Re: [RFC PATCH 02/15] cxl/core/hdm: Bail on endpoint init fail
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Sender: Luis Chamberlain <mcgrof@infradead.org>

On Fri, May 13, 2022 at 12:14:51PM -0700, Dan Williams wrote:
> On Fri, May 13, 2022 at 8:12 AM Luis Chamberlain <mcgrof@kernel.org> wrote:
> > But with CONFIG_FAIL_FUNCTION this means you don't have to open code
> > should_fail() calls, but instead for each routine you want to add a failure
> > injection support you'd just use ALLOW_ERROR_INJECTION() per call.
> 
> So cxl_test takes the opposite approach and tries not to pollute the
> production code with test instrumentation. All of the infrastructure
> to replace calls and inject mocked values is self contained in
> tools/testing/cxl/ where it builds replacement modules with test
> instrumentation. Otherwise its a maintenance burden, in my view, to
> read the error injection macros in the nominal code paths.

Is relying on just ALLOW_ERROR_INJECTION() per routine you'd want
to enable error injection for really too much to swallow?

  Luis